Lighting fixture having load supporting conductors



March 25, 1958 J. w. LINCOLN 2,828,409

LIGHTING FIXTURE HAVING LOAD SUPPORTING CONDUCTORS Filed Jan. 20, 1955LIGHTING FIXTURE HAVING LOAD SUPPORTING CONDUCTORS John W. Lincoln,South Lincoln, Mass.

Application January 20, 1955, Serial No. 483,031

Claims. (Cl. 240-78) This invention relates to electrical conductors andmore particularly to electric lighting fixtures in which the supportingmembers for the fixture serve as electrical conduits.

In current practice it has been considered essential to use independentwires to carry the electrical current from the usual outlet in theceiling or wall of a building to the lighting socket in the chandelieror lighting fixture. Such wiring is sometimes run through a hollow pipeor tubing from one or more elements of the lighting fixture for purposesof concealing it or it may be carried exteriorly of the fixtureelements. In either case, the insulation frequently deteriorates causinghazardous conditions or an unsightly appearance. While it has beenproposed in U. S. Patent to Maxim 247,086 to pass the electrical currentthrough a structural element of a lighting fixture, no satisfactorymeans for insulating such a device has been known. Furthermore, it isimportant to provide safe and neat connections for supporting arelatively heavy fixture of the type disclosed from the conventionalceiling box.

A primary object of the invention, therefore, is to provide an improvedmulti-socket lighting fixture having no separate wiring.

A further object of the invention is to provide a chandelier in whichone group of supporting elements of the chandelier serves as a conductorfor one side of the line and another group of the chandelier elementsserves as the electrical conductor for the other side of the line.

A further object of the invention is to provide an improved chandelierand ceiling fixture completely coated with an insulating material.

Further objects will be apparent from the specification and drawings inwhich:

Fig. l is an elevation partly broken away showing a preferred embodimentof my improved chandelier,

Fig. 2 is a bottom view of a part of the structure of Fig. 1,

Fig. 3 is an enlarged detail showing one of the lamp sockets,

Fig. 4 is an enlarged sectional detail showing parts of the chandelier,and

Fig. 5 is an enlarged fragmentary detail, partly sectioned, of thechandelier of Fig. 1.

The invention comprises essentially the provision of a chandelierstructure constructed of solid metallic elements which extend from acentral junction to the various lamp sockets. In the preferredembodiment, I provide a group of upper arms which radiate from a commonhub to a plurality of lamp sockets positioned at various laterallocations from the hub. A second group of radiating arms connects thelamp socket to a lower hub which is in turn connected to the upper hub.Two hangers secured to the upper hub suspend the entire assembly from anoverhead box customarily used for ceiling lighting fixtures. The centerportions of the hubs are made of insulating material so that the uppergroup of radiating "ice arms serves to conduct current to the lampsockets from one of the upper hub hangers. The other upper hub hanger iselectrically connected through the hub to the lower hub and thencethrough the lower radiating arms to the lamp sockets to complete thecircuit to each lamp. Insulation is provided by means of a hard, toughcoating of synthetic plastic material such as polyethylene or'the like.

Referring now more particularly to the drawings, the ceiling box is ofconventional construction and has a central post 11 on which there isthreaded a coupling 12 which extends downwardly below ceiling 13. Thecustomary electrical leads 14 and 15 are carried into the ceiling box 10through an aperture 16. The canopy 17 supports the chandelier indicatedgenerally at C by means of insulating bushings 18 and 19 secured to thecanopy by nuts 20 and 21. Cap nut 22 supports the canopy and chandelierassembly from coupling 12. The chandelier assembly C is supported by apair of brackets or hangers 25 and 26 insulated by a coating 27 on eachhanger and anchored in the couplings 18 and 19 by collet extensions 28,28 and jam nuts 29, 29. Each of the hangers serves as an electricalconductor and is connected tothe leads 14 and 15 at the ceiling box 10by means of connectors 30, 30. The lower termini of hangers 25 and 26are secured in a hub-like member 31 to provide the entire support forthe chandelier structure. Hub 31 is constructed of an insulatingmaterial and it will be seen in Fig. 4 that the lower face of the hubcomprises an annular conducting ring 32 which is electrically connectedto conductor 26 by means of a stud 33 and a coupling 34. Conductor 25 iselectrically connected to the central supporting hanger 35 throughcollar 36 and strap 37 which is clamped against collar 36 by means of acap screw 38. Strap 37 extends under the nut 39 on the upper end ofhanger 35 thus completing the electrical circuit to the hanger. Aplurality of radiating arms 40, 40 are anchored in the annularconducting ring 32 and extend radially outwardly and downwardly toterminate at the lamp sockets 45, 45. The hub assembly 31 as well asradiating arms 40 are coated with an insulating synthetic plasticmaterial 46 which in efifect is a continuation of the plastic coating 27on brackets 25 and 26.

If desired the lamp sockets (Fig. 3) are formed of a central mandrel 50around which several turns of the arms 40 are wrapped to form thethreads for the bases of lamps 51, 51. The insulation from the ends ofthe arms 40 is removed to provide suitable electrical contact with thelamps 51. The circuit to each of the lamps is completed through acorresponding set of lower radiating arms 55, which lead centrallythrough each of the mandrels 50, where the exposed ends of the arms 55contact the central posts of the lamp bases, to a lower hub 56 as shownin Fig. 5. This lower hub 56 has an electrically conductive core 57 towhich each of the arms 55 is connected. Hanger 35 terminates in core 57to complete the electrical circuit from conductor 25. Core 57 iscompletely insulated in hub 56 by means of a seal or cap 58. The arms55, hub 56 and hanger 35 are likewise all covered with a suitableinsulating covering 59.

The structural elements of my improved chandelier may be solid ortubular or of any desired cross section such as circular, polygonal,oval as may be desired. The various elements may be precoated beforeassembly or the entire chandelier may be dipped after assembly. In thismanner I provide an extremely rugged lighting fixture which is notsubject to short circuits due to deterioration of the insulation of theelectrical wire and in addition it is not necessary to thread wires forthe individual lamp sockets through a maze of tubular elements havingsharp a 3 internal bends and corners that render threading diflicult andcutting of insulating frequent. The assembly is extremely safe, simpleto manufacture and will outlast the conventionally wired lightingfixture. While polyethylene has been mentioned above as an example of asuitable material many syn hetic resins can be employed depending uponthe particular requirements. The acrylic resins, vinyl chloride resinplastigels and the synthetic rubber derivitives are among the numerousmaterials which can be used to provide various color and artisticeifects. Furthermore it will be understood that the invention is notlimited to chandeliers, but may be applied equally to wall brackets,floor lamps, desk lamps and lighting fixtures in general.

Having thus described my invention, I claim:

1. A ceiling lighting fixture assembly comprising a plurality ofelectric lamp sockets, a first hub, a set of radiating arms connectingand supporting the sockets to said hub, a second hub, a set of radiatingarms connecting and supporting the sockets to said second hub, a hangervertically extending between said hubs, a canopy, a pair of hangersextending vertically between the first hub and said can py, One of saidlast named hangers conducting electrical current to the sockets throughthe first set of radiating arms and the other of said hangers conductingelectrical current to the sockets through the hanger between the hubsand the second set of radiating arms, and

an insulating covering for the hangers and both sets of radiating arms.

2. A fixture according to claim 1 having an insulating collet forsecuring each of the upper hangers to the canopy.

3. A fixture according to claim 1 in which the sockets are formed by theradiating arms.

4. A fixture according to claim 1 having an electrically conductiveconnection between one of the upper hangers and the hanger between thehubs through the first hub.

5. A fixture according to claim 1 in which the first hub comprises aring of insulating material, a second annular ring of electricallyconductive material in which the first set of radiating arms areanchored, an electrical connection between one of the hangers and saidsecond annular ring, a clamping post extending through the rings, and anelectrical conductor connecting the other of the hangers with saidclamping post.

References Cited in the file of this patent UNITED STATES PATENTS MossFeb. 12, 1935

